Automatic luminance and contrast adustment for display device
First Claim
1. An apparatus for automatically controlling a display luminance and contrast of a display device, the apparatus comprising:
- a) an illumination measuring mechanism for measuring a display illumination of a display device;
b) a surround luminance measuring mechanism for measuring a surround luminance of the display device;
c) a calculating mechanism for calculating a current display luminance and a current contrast setting for the display device;
d) a determining mechanism for determining a change in the display illumination and a change in the surround luminance based on measurements performed by the illumination measuring mechanism and the surround luminance measuring mechanism, respectively;
e) a luminance adjustment mechanism for calculating an updated display luminance when the determining mechanism determines that a change in the display illumination has occurred, and for adjusting the display luminance of the display device based on the updated display luminance to display an image; and
f) a contrast adjustment mechanism for calculating an updated image contrast when the determining mechanism determines that a change in the surround luminance has occurred, and for adjusting the image contrast on the display device based on the updated contrast setting to display the image;
wherein;
the current display luminance is replaced with the updated display luminance and the current contrast setting is replaced with the updated contrast setting;
the luminance adjustment mechanism calculates the updated display luminance based on the change in display illumination, and further performs a progressive time dependent adjustment of the display luminance based on whether the updated display luminance is higher or lower than the current display luminance;
the luminance adjustment mechanism performs the progressive time dependent adjustment based on a degree of light adaptation when the updated luminance is higher than the current display luminance; and
the luminance adjustment mechanism performs the progressive time dependent adjustment based on a degree of dark adaptation when the updated luminance is lower than the current display luminance.
4 Assignments
0 Petitions
Accused Products
Abstract
An apparatus and method is provided for dynamically modifying both the luminance and contrast of an image as it is displayed on a display unit in response to changing lighting conditions. Sensors are utilized to continually measure the luminance of the light illuminating the display unit and the display surround luminance. Measurement signals generated by the light sensors are processed to provide display luminance and contrast adjustment control signals that gradually cause the adjustment of the display unit'"'"'s luminance and contrast in response thereto. Continual adjustment of the luminance and contrast of a display unit according to changing lighting conditions such that the brightness and contrast perception of the displayed image remains constant under the varying conditions. As a result, a number of advantages our obtained including: the brightness and contrast perception of images displayed on a display unit remains constant as the display device illumination changes; the brightness and contrast perception of images displayed on a display unit remains constant as the display unit surround luminance changes; and power consumption is decreased in dim environments.
-
Citations
4 Claims
-
1. An apparatus for automatically controlling a display luminance and contrast of a display device, the apparatus comprising:
-
a) an illumination measuring mechanism for measuring a display illumination of a display device;
b) a surround luminance measuring mechanism for measuring a surround luminance of the display device;
c) a calculating mechanism for calculating a current display luminance and a current contrast setting for the display device;
d) a determining mechanism for determining a change in the display illumination and a change in the surround luminance based on measurements performed by the illumination measuring mechanism and the surround luminance measuring mechanism, respectively;
e) a luminance adjustment mechanism for calculating an updated display luminance when the determining mechanism determines that a change in the display illumination has occurred, and for adjusting the display luminance of the display device based on the updated display luminance to display an image; and
f) a contrast adjustment mechanism for calculating an updated image contrast when the determining mechanism determines that a change in the surround luminance has occurred, and for adjusting the image contrast on the display device based on the updated contrast setting to display the image;
wherein;
the current display luminance is replaced with the updated display luminance and the current contrast setting is replaced with the updated contrast setting;
the luminance adjustment mechanism calculates the updated display luminance based on the change in display illumination, and further performs a progressive time dependent adjustment of the display luminance based on whether the updated display luminance is higher or lower than the current display luminance;
the luminance adjustment mechanism performs the progressive time dependent adjustment based on a degree of light adaptation when the updated luminance is higher than the current display luminance; and
the luminance adjustment mechanism performs the progressive time dependent adjustment based on a degree of dark adaptation when the updated luminance is lower than the current display luminance.
-
-
2. An apparatus comprising:
-
a) imaging means for generating electronic image data corresponding to an imaged scene;
b) a display means for displaying the electronic image data generated by the imaging means;
c) illumination measuring means for measuring a display illumination of a display device;
d) surround luminance measuring means for measuring a surround luminance of the display device; and
e) control means for controlling a display luminance and contrast of the display means, wherein said control means includes;
i) calculating means for calculating a current display luminance and a current contrast setting for the display device;
ii) determining means for determining a change in the display illumination and a change in the surround luminance based on measurements performed by the illumination measuring means and the surround luminance measuring means, respectively;
iii) luminance adjustment means for calculating an updated display luminance when the determining means determines that a change in the display illumination has occurred, and for adjusting the display luminance of the display device based on the updated display luminance to display an image; and
iv) contrast adjustment means for calculating an updated contrast setting when the determining means determines that a change in the surround luminance has occurred, and for adjusting the contrast of the display device based on the updated contrast setting to display the image;
wherein;
the current display luminance is replaced with the updated display luminance and the current contrast setting is replaced with the updated contrast setting;
the luminance adjustment means calculates the updated display luminance based on the change in display illumination, and further performs a progressive time dependent adjustment of the display luminance based on whether the updated display luminance is higher or lower than the current display luminance;
luminance adjustment means performs the progressive time dependent adjustment based on a degree of light adaptation when the updated luminance is higher than the current display luminance; and
the luminance adjustment means performs the progressive time dependent adjustment based on a degree of dark adaptation when the updated luminance is lower than the current display luminance.
-
-
3. A method of controlling a display luminance and contrast of a display device comprising:
-
a) measuring a display illumination of a display device;
b) measuring a surround luminance of the display device;
c) calculating a current display luminance and a current contrast setting for the display device;
d) determining a change in the display illumination and a change in the surround luminance;
e) calculating an updated display luminance when a change in the display illumination has occurred;
f) adjusting the display luminance of the display device based on the updated display luminance to display an image;
g) calculating an updated contrast setting when a change in the surround luminance has occurred;
h) adjusting the contrast of the display device based on the updated contrast setting to display the image; and
i) replacing the current display luminance with the updated display luminance and the current contrast setting with the updated contrast setting;
wherein;
the updated display luminance is calculated based on a change in display illumination, and a progressive time dependent adjustment of the display luminance is performed based on whether the updated display luminance is higher or lower than the current display luminance;
the progressive time dependent adjustment is performed based on a degree of light adaptation when the updated luminance is higher than the current display luminance; and
the progressive time dependent adjustment is performed based on a degree of dark adaptation when the updated luminance is lower than the current display luminance.
-
-
4. An apparatus for automatically controlling a display luminance comprising:
-
a) means for measuring display illumination;
b) calculating means for calculating a current display luminance based on the measured display illumination;
c) determining means for determining a change in the display illumination based on measurements performed by the means for measuring display illumination; and
d) luminance adjustment means for calculating an updated display luminance when the determining means determines a change in the display illumination has occurred;
wherein the luminance adjustment means calculates the updated display luminance based on the change in display illumination and performs a progressive time dependent adjustment of the display luminance based on whether the updated display luminance is higher or lower than the current display luminance;
wherein the luminance adjustment means performs the progressive time dependent adjustment based on a degree of light adaptation at a first rate when the updated luminance is higher than the current display luminance; and
wherein the luminance adjustment means performs the progressive time dependent adjustment based on a degree of dark adaptation at a second rate which is slower than the first rate when the updated luminance is lower than the current display luminance.
-
Specification